Today I learned about something called the Oddy Test. Named after the man who invented it in the 70s, its used to determine whether a material can be safe to use with artefacts. While a material or foam may be useful for storing an object, if its made of the wrong stuff it could damage the piece without you realising until its too late. So before using it you can check it with the Oddy test.
The way it works is the piece of material in question is mashed up and put in a test tube, along with some distilled water and a strip of copper, silver and lead. Metal with water is in another tube next to it to control the experiment. This is heated in an oven for about a month, which speeds up the test to see the materials long term effects; alternately you can just put the stuff in the tubes and wait 6 months. During this time gasses are released from the material, and depending on the condition of the metals you can identify what chemicals are in your cloth!